Radio broadcasting and communication system



MarCh 9, 1937.

N. C. THYSON RADIO BROADCASTING AND COMMUNICATION SYSTEM Filed May 20,1933 Nil/0M0 65 723: Wzum Patented Mar. 9, 1937 UNITED STATES 3 Claims.

My invention relates to improvement in radio broadcasting andcommunication systems, and particularly to an electrical-mechanicaldevice, and associated system, intended to be incorporated with a radioreceiving instrument, wireless telegraph or telephone receiver, or anyother piece of receiving communication apparatus having connection withor adapted to be influenced by a central station or power supply.

An object of my invention is to provide apparatus by which, in the eventof any emergency, personal, group, local, state-wide, national, orinternational, or any other occasion arising where it is desired toestablish instant communication with a large number of radiobroadcasting receivers, or other communication apparatus, this can bedone from a central point, as for instance a central power plant, andany number of broadcasting receivers will be automatically put intooperation to transmit and communicate any desired message or matter.

Another object is to so construct and interconnect the parts that, eventhough the radio broadcast receiver, or other receiving apparatus, be

. turned off or inoperative, a slight variation in the power voltage ofthe operating current, or a variation in other actuating or controlmedium, will render the individual broadcaster instrument operative, thereceiver being automatically turned 0 on, and the parts serving toautomatically turn ofi the alarm or message receiving circuits and torestore the circuits and connections to a normal operating hookup forfuture or normal use.

Still another object is to provide automatic circuit selective means,tuning means, or other selective control means by which the normalcircuits and connections of a radio broadcast receiver, or otherinstrument, will be automatically disconnected and the instrument willbe tuned to receive the message or matter transmitted by a master orpredetermined station.

Yet another object is to provide means by which the volume of the sound,warning, or message, as transmitted and broadcast under theautomatically accomplished setting, will always be maintained at orabove a certain predetermined volume.

A further object is to provide a device of this character that can beinstalled in and associated with receiving instruments in number withoutlimit, and which can be tuned to any desired broadcasting ortransmittingapparatus, and can be automatically connected in operative relation anddisconnected, through supply of slight overvoltage, or undervoltage, orthrough other slight PATENT OFFICE aAnIo BROADCASTING AND COMMUNICA-Tron SYSTEM l Nimmo C. Thyson, Miami, Fla.

Application May 20, 1933, Serial No. 672,078

variation in operating conditions at a power house or other likestation.

With the above and other objects in view, which will be apparent tothose skilled in the art, my invention includes certain other featuresof construction and. combinations and arrangements of parts and ofsystems, which will be hereinafter set forth in connection with thedrawing and then pointed out in the claims.

In the drawing:

Figure l is a diagrammatic view showing one adaptation of my invention.

Fig. 2 is a fragmentary view illustrating a modified construction of oneof the parts.

In the present instance I have illustrated an embodiment of my inventionincluding a radio broadcast receiver of the power operated type, andthis apparatus contemplates use. with one particular synchronizedstation to which the apparatus is calibrated or set, as well as theusual mechanism for tuning in or adjustment for various stations,ordinarily now embodied in broadcast receiving apparatus. My inventionfurther contemplates the supply of operating current, or other actuatingenergization, from a central and controlled point or station, which canbe-the ordinary central electric station or power generating plant.

A conventional, or special, radio broadcast receiving apparatus can beemployed, and in the present instance this might be housed in the caseas diagrammatically indicated at I. Any suitable radio detecting orreceiving and tuning circuit and hook-up can be employed, and,therefore, no attempt is here made to particularly illustrate theseparts or any particular circuit arrangement or control means therefor.Many types of circuits and hook-ups for radio broadcast receivers arenow well known and successfully operated, and from time to time theseare being changed and improved. It is not necessary that my inventionrely upon any particular form or hook-up of radio receiver, orapparatus, and it now appears that the invention is operative withsubstantially any type of receiver, whether it be radio or wirelesstelephone, wireless telegraph or wireless television, or cable telegraphor telephone, or some other special form of receiver.

It is essential that my invention include, and embody with the receiver,a-control switch or other control mechanism operable from a centralstation, and means to insure proper operation of the broadcast receiverthus energized or rendered operative. Power lines 2 and 3 lead from acentral power plant, or other suitable source oi. energy supply, andthese power lines can be connected to receive power from a generator,from batteries, or from any other suitable source of supply of current,which current can be held to be substantially consistent in itscharacter and can be slightly varied when desired, as for instance heldat substantially uniform voltage for normal operation and can yet beslightly lowered or slightly raised in its voltage when desired. Suchpower generating plants and controls for holding consistent voltage andfor decreasing or increasing the voltage are old and well known in manyforms and no attempt is here made to even diagrammatically illustratethe same. The power lines or wires 2 and 3 are extended into the set at4 and 5, and are connected as the operating current input forthe set inany desired manner, depending upon the particular circuit or hook-upused. So many circuits and hookups are now in use and are adaptable,that no attempt is here made to illustrate any particular arrangement,and the audions, transformers, and other parts of the receivingapparatus, together with the circuit connections therefor, can beconsidered as being enclosed in the case generally indicated at 6. Aswitch is provided in the power supply lines to permit manual control ofthe operating circuit input, which also can be of standard or anydesired arrangement and connection.

A highly sensitive relay 8, which can be of the voltmeter type, has ahigh resistance unit 9 connected by shunt circuit l0 and H with thepower lines 2 and 3, to thus shunt around the circuit 7. This unit 9 ismade of high resistance to thus cut down current consumption to aminimum required for actuation of the highly sensitive relay 8, and theinfluenced member l2 of this relay is made in the form of a switch arm,

carrying armature l3.

The relay 8 is intended primarily to catch and be influenced by slightdropping, or increase, of the voltage, or other slight variations in thecharacter of the current supply through the lines 2 and 3, and it isessential that the relay 8 be readily responsive to. only slightvariation such as will not influence the operation of or cause damage tothe broadcast receiving apparatus, or

- to other appliances or instruments that may be connected with andoperated from the power lines. Further, it is desirable that this relay8 have such high resistance that only a very slight consumption ofcurrent is required, and the exe pense of constant connection is thusmade almost negligible.

The primary object of the relay 8 is to respond to slight variations inthe current supply and then actuate switch relay l4, influencing L thetuning and the volume control circuits of the broadcast receiver. Thisrelay switch l4 accomplishes the double function of automatically tuningthe receiver to the settings required for the master station andautomatically cutting 165 out any manually set tuning, whether the radioreceiver is in operation or has been disconnected through manual openingof the switch 1. If switch is opened, thus disconnecting the operatingcurrent input to the set, relay switch l4 establishes an input currentconnection predetermined volume to signals broadcast through the speakerl5, or other suitable unit.

A relay core l6 has a coil thereon, and this coil has one terminalconnected through wire |8 with current supply line wire 3, a wire I9from the other end of the coil 1 is connected with contact 20 carried bythe voltmeter relay, and a similar contact 2|, spaced from contact 20,has a wire 22 extending therefrom to connect with the other wire 2 ofthe line circuit connections. These contact members 20 and 2| are solocated that as the arm l2 swings through reduction in the voltagethrough coil 9, the armature or cross contact piece l3 will engage bothof the contact pieces 20 and 2|, in consequence of which a circuit isestablished directly from the line connections 2 and 3 through the coilH.

A switch arm 23, pivoted at 24, has limited swinging movement as shownby the full and. dotted lines in Figure 1, and a spring 25, or othersuitable means, is provided to normally yieldably hold the switch arm inone position in which it is separated from the adjacent end of core l6.An armature bar 26 is provided on this switch arm 23, which arm ispreferably of insulated material or has the several portions carriedthereby insulated therefrom. As the circuit through coil H isdeenergized, with the normal voltage current passing through relay 8 andthe arm |2 thereof in the position shown by full lines, spring 25normally urges the arm 23 to the full line position in Figure l.

The usual variable condenser 21, or any other suitable tuning or settingmeans, is provided for manipulation to tune the machine and select theparticular station setting desired, and this mechanism at 21 can bemanually manipulated or can be operated in any other desired manner. Thetuning circuit wires 28 and 29 are connected in the detector circuit ofthe usual radio receiving hook-up, and wire 29 connects with while wire28 is led through the variable condenser 27 and this connects withcontact piece 3|. These contact pieces are mounted in spaced relationadjacent to the swinging end of arm 23, and a cross connector bar 32 onthis arm 23 is positioned to engage with the spaced contact pieces-30and 3| and complete the tuning circuit through variable condenser 21,under normal operating conditions, when the swung to the full lineposition under the influence of spring 25.

Tuning circuit wires 33 and 34 are led off from wires 28 and 29 toconnect with spaced contacts 35 and 36, this shunt tuning circuit beingclosed by cross contact bar 31, when the switch arm 23 is moved to thedotted line position, under influence of current passing through thecoil ll. When the main tuning circuit is closed, this shunt tuningcircuit is open, and the reverse. A fixed condenser 38, or other tuningmeans, is connected in this shunt tuning circuit including wires 33 and34, and this fixed condenser or tuning means is so fixed and so set thatwhen the shunt tuning circuit is closed the receiving set is tuned tothe master broadcasting station, or other station from which thesignalsto be automatically picked up will be transmitted. While I speakof a fixed condenser 38, it will be appreciated that this might be avariable or settable condenser, or other tuning means, and that the termfixed is here used only as indicating setting or calibration with thetransmitting station.

The usual volume control rheostat 39, settable a contact piece 39,

switch arm 23 is to control the volume through the speaker IE3, or otherannunciator, has circuit. wires 40 and 4| connected therewith, and thesewires will be connected in usual manner with the speaker I5 and with theset output, generally indicated at 42. Often the control rheostatisadjusted to cut down the volume through the speaker l5, and it isdesirable that arrangements be made to insure a predetermined volume ofany signals or other matter broadcast or sent throughthe automatic.system. With this inmind, the volume circuit wire 43 leads from wire 4|to connect with contact 44, and the circuit wire 45 leads fromspacedcontact 45 to connect directly with the controlrheostat 39 at apoint where the resistance is sufficiently low to give the desiredvolume atthe speaker l5. A cross connecting bar- 41 is provided onswitch arm 23 to bridge contacts 44 and 46 and complete the automaticcontrol shunt circuit. This connection of the control shunt circuitinsures a predetermined volume of sound from the speaker l5, and ifperchance the manually settable arm of the rheostat .39 be adjusted forgreater volume, the current will take the course of least resistance andthe volume will'be-thus increased.

An automatic line shunt circuit is made .up of wires 48 and 49connecting with wire 2 of the power supply line, to bridge aroundmanually operated switch I, and these wires48 and 49 are connected withspaced contacts 56 and 5|, a bridge contact bar 52 being provided on,switch arm 23 to close across these spaced contacts 50 and 5| and thuscomplete the main line shunt circuit.

As stated, the receiving circuit and hook-up can be arranged in anydesired and approved manner, and my invention will necessarily be variedin the arrangement and connection of its parts to suit the particularreceiving apparatus, in view of which it will be appreciated that thepresent disclosure is intended only to show one adaptation of theinvention.

With this arrangement of the parts, the voltmeter relay arm |2 normallyassumes or cupies the position shown by the full lines in Figure l, andthis position will be maintained by the constant flow of current throughresistance coil 9. The main current supply circuit connections are thenmanually controllable through switch and as switch arm 23 is normallyheld in the full line position, illustrated in Figure 1, by spring 25,the circuit through variable tuner 21 is completed. Volume controlrheostat 39 can be operated in the usual manner, and in fact thebroadcast receiving instrument, or other apparatus, can be used,adjusted and operated in the ordinary manner. When switch I is closedthe current input to the set will be operatively connected, and whenswitch is open, as illustrated in Figure 1, the operating current inputcircuit is not energized. Otherwise, the parts remain in substantiallythe same relation, and irrespective of whether the receiver is in use,or the operating current input is cut ofi, the receiver is available forthe automatic reception of master or alarm signals or messages.

Assuming now that it is desired to adapt the receiver to send signals orinformation coming from the master sending station, the current voltageat the power house, or other suitable current supply source, is slightlylowered, and the effective variation through coil 9 causes arm |2 toassume the dotted line position as indicated in Figure 1, where armaturecross bar l3 bridges across and connectscontacts 20 and 2|. Thisenergizes the circuit through coil I! in consequence of which switch arm23 is moved to the dotted line position shown in Figure 1. This swingingmovement of the switch arm 23 breaks the tuning circuit through variablecondenser 2i, but completes the circuit connection through fixedcondenser 38,. to thus tune. the instrument for reception of thepredetermined station signals, waves, or other matter. The swingingmovement of arm 23 closes the line controlled circuit through contacts50 and in consequence of which the power circuit is completed forthepassage of operating current to the in-.

put. r

As switch arm 23 is moved to close connector 7 bar 41 across contacts 44and 46, the circuit having the predetermined setting of the volumecontrol rheostat is energized, as well as the circuit through theregular connections to'the rheostat.

As the connection of fixed condenser 38 automatically tunes thereceiving apparatus to take signals-from-the master orpredeterminedstation, and the input operating current circuit is completed, thereceiving apparatus is almost instantly available to receive andannunciate, through speaker I5, any desired signal, instructions, or anyother matter as broadcast from the master or predetermined station. Thefixed connection to the volume control rheostat insures that the signalscoming in over the automaticallyconnected circuit will be of fullpredetermined ,volume. When the restoration of the parts is desired, itis only necessary to slightly increase the voltage through the lineconnections 2 and 3, to bring this back to the predetermined normal andthe arm l2 will then immediately assume the full line position of Figure1, thus breaking the connection through the coil l1 and permittingswitch arm 23 to move back to the full line position. The receiving setis then restored 'to normal settings and can be tuned, operated, andotherwise used in ordinary manner. Thus it will be seen that both thepredetermined tuning and connection, and the restoration to normalcondition, are automatically accomplished from the central station.

In the diagrammatic illustration in Figure 1, the main and shunt tuningcircuits are indicated by light lines, and all other circuits by heavierlines, as this may aid in tracing and following the various circuits.

As illustrated in Fig. 2, a second set of contacts 53 and 54 might beprovided on relay 8 and connected by suitable circuit wires with thewires l9 and 22, a cross connecting bar 55 being provided on the arm |2to bridge across these contacts 53 and 54 and complete the circuittherethrough. With this arrangement, overvoltage in the current supplylines will cause the arm I2 to swing to a position in which the spacedcontacts 53 and 54 are bridged by contact piece 55. One or both sets ofautomatic control contacts might be used on the relay 8, and the systemcan thus be controlled automatically by increasing or decreasing thevoltage, or with the use of the two sets of contacts, by any variationone way or the other from the normal line voltage of the power lineconnections.

Where apparatus as above set forth is applied and adapted to radioreceiving sets, or other reor at various points throughout a State,throughout the United States, or throughout the world, parties desiringto accomplish automatic connec- 5 tion of the so equipped receivingapparatus need only seek the cooperation of the central power station tovary the power supply current; or, perhaps later developments may showsome manner in which broadcast ether waves or other energy can beemployed to vary this current suificiently; and then, the receivingapparatus is almost instantaneously set and adjusted to receive from oneor more predetermined central broadcasting or sending stations. Withthis apparatus and system alarm and warning broadcasts, speeches ofgeneral interest, announcements of public import, and in fact anysignal, message, announcement or the like, can be instantaneously andautomatically conveyed to be reproduced and audibly projected withpredetermined volume, at a great number of receiving points, and in factfrom every receiving instrument within reach of the control and thebroadcasting systems.

The voltage increase or decrease, or the variation of the current in theline wires 2 and 3 can be accomplished in any manner desired, but in thediagrammatic showing in Figure 1 I have illustrated a switch 56 in thepower supply line that can be shifted to connect with a line supplyingcurrent of higher or lower voltage, or otherwise current so varied as tocause actuation of the highly sensitive relay 8 or 8', as the case maybe.

While I have herein shown and described only certain specificembodiments of my invention and have set forth only certain possiblemodifications, it will be appreciated that many changes and variationscan be made in the form, construction and arrangement of the parts, inthe circuit connections and hook-ups, in the plan and mode'of operation,and in other respects, without departing from the spirit and scope of myinvention.

Iclaim:

1. A broadcast receiver comprising, line cir- 4 cuits to supply variablepower to the receiver, a

ceiving apparatus, at various points in a locality manually actuatableswitch to cut out the power supply, a shunt circuit including a relay toautomatically close the circuit to the receiver when the power supply inthe main lines is varied, means also operable by variations in the powersupply to tune the receiver to a predetermined setting, and volumecontrol means also operable by variations in the power supply to insurea predetermined volume of sound when the power supply is varied.

2. A broadcast receiver comprising, a radio receiver, line circuits tosupply operating power to the receiver, a shunt circuit connected withsaid line circuits, a switch in the circuit to the receiver, means tonormally hold said switch open,

relay means in said shunt circuit operated by variations in the currentsupply from the main circuit to cause said switch to be closed to thuscomplete the operating current supply circuit to the radio receiver, andvolume control means also operable by variations in the power supply toinsure a predetermined volume of sound when the power supply is varied.

3. A broadcast receiver comprising, a radio receiver, line circuitstosupply variable power to said receiver, a manually actuatable switchto control the power supply, a shunt circuit to the receiver around saidmanually actuatable switch, a switch in said shunt circuit, means tonormally hold said switch open, a switch controlled shunt circuitconnected with said shunt line circuits in advance of the manuallyactuatable switch, a magnet in said switch controlled shunt circuit toclose the switch of the shunt circuit to the radio receiver when themagnet is energized, said last mentioned parts constituting relay meansfrom said switch controlled shunt circuit to automatically close thecircuit to permit flow of current to the magnet and consequently closethe shunt circuit to the radio receiver when the power supply in themain lines is varied, and volume control means also operable byvariations in the power supply to insure a predetermined volume of soundwhen the power supply is thus varied.

NIMMO C. TI-IYSON.

